"The death of this young man on board a Metro Transit vehicle is tragic and appalling. Unfortunately, life on the bus reflects life on the streets. Nationally, and even here at home, we've experienced acts of outrageous violence in recent weeks," Indrehus said.

Indrehus said Metro Transit is continuing to beef up security measures.

"We're hiring more police officers, increasing our on-board police presence on vehicles, improving our on-board camera system and continuing to work with our law enforcement partners," he said.